UCAT Decision Making Syllogisms: A Step-by-Step Solving Method

Decision Making gives you 31 minutes for 35 questions. Roughly a third of those are syllogisms, which means you have about 53 seconds per question and zero time to argue with yourself about what “some” technically means. The students who score in the 700s on DM are not faster readers. They have replaced reading with drawing. They glance at the premises, sketch two or three overlapping circles in their head, and check four conclusions against the picture in under a minute.

This guide walks through the exact method, why it works, where most candidates lose marks, and a 20-question drill plan to lock it in.

What a UCAT syllogism actually looks like

A DM syllogism gives you two or three premises followed by four conclusions. You decide which conclusions must follow from the premises. Sometimes one, sometimes two, sometimes none.

A typical stem reads like this: “All cardiologists are doctors. Some doctors are surgeons. No surgeons are paediatricians.” You then get four “Yes” or “No” decisions to make about claims such as “Some cardiologists are surgeons” or “No paediatricians are cardiologists.”

Three things matter here.

1. The words all, some, no, and some are not are doing all the work. Everything else is a distractor. “Cardiologist” could be “blibblat” and the logic would not change.
2. You only accept conclusions the premises force. If something is merely possible, the answer is No. UCAT does not reward guessing the most likely real-world outcome. It rewards reading the premises as a closed system.
3. The conclusions are designed to exploit the gap between everyday English and formal logic. The UCAT Consortium’s official practice on ucat.ac.uk is the cleanest place to see how brutally they apply this. Two full official mocks plus the question bank in the testing interface should be your benchmark, not anyone’s interpretation of it.

The 4 valid conclusion types

Every claim a syllogism makes boils down to one of four shapes. Memorise these and your brain stops translating mid-question.

The letters A, E, I, O are the traditional Aristotelian labels. You do not need to know that for the test, but having a label for each shape is faster than reading the sentence again.

Two things trip people up here:

• “Some” in UCAT logic means at least one, possibly all. So “some doctors are surgeons” is true even if every doctor is a surgeon.
• “Some A are not B” is not the opposite of “some A are B”. They can both be true at the same time.

Mapping premises with circles, not words

The technique is borrowed from Euler and Venn diagrams. Draw a circle for each category. Position them based on what the premise forces.

• All A are B: draw circle A entirely inside circle B.
• No A are B: draw two separate circles that do not touch.
• Some A are B: draw two circles that overlap, and put a dot or an X in the overlap to remember “at least one lives here”.
• Some A are not B: draw two overlapping circles, and put a dot in the part of A that sits outside B.

The reason this beats reading is that English carries assumptions your brain fills in automatically. “Some students study Latin” sounds like it implies “some do not”, which is not a logical entailment. The circles do not care about implications. They only show what the premises put on paper.

When you have three categories, draw three circles. Place them based on the strictest premise first (“no” or “all”), then layer the weaker premises (“some”) on top. If the diagram cannot accommodate a conclusion in any layout, the conclusion is forced. If you can redraw the diagram in a way that breaks the conclusion, the answer is No.

The “all, some, none” translation trick

Premises in DM rarely arrive in clean A/E/I/O form. They wear costumes. Your first job is to strip the costume off before drawing anything.

• “Every nurse owns a stethoscope” becomes All nurses are stethoscope-owners.
• “Not a single registrar drives a Tesla” becomes No registrars are Tesla-drivers.
• “At least one medical student lives in Carlton” becomes Some medical students are Carlton-residents.
• “There are anatomy tutors who do not teach histology” becomes Some anatomy tutors are not histology-teachers.

Watch out for double negatives, conditionals, and “only” statements. “Only doctors can prescribe morphine” does not mean “all doctors prescribe morphine”. It means all morphine-prescribers are doctors. The arrow runs the other way, which leads directly into the most common trap.

Why “all A are B” does not mean “all B are A”

This is the single highest-yield idea in the entire syllogism section. The reverse of “All A are B” is not “All B are A”. It is “Some B are A”, and only if at least one A exists.

If all cardiologists are doctors, you cannot conclude that all doctors are cardiologists. You can conclude that some doctors are cardiologists (assuming the premises imply cardiologists exist), but the universal claim about doctors is unsupported.

The same applies to “No A are B”. This one does flip safely. If no surgeons are paediatricians, then no paediatricians are surgeons. The “no” relationship is symmetric. “All” is not.

“Some A are B” also flips safely. If some doctors are surgeons, some surgeons are doctors. But “some A are not B” does not flip. “Some doctors are not surgeons” does not entail “some surgeons are not doctors”.

If you remember nothing else, remember this: No and some are flip freely. All and some are not do not. r/UCAT threads on DM strategy come back to this point constantly because it is where two or three marks consistently leak out of otherwise strong attempts.

Walking through three example syllogisms

Here is the method end to end on three realistic stems.

Example 1

Premises: “All radiologists are doctors. No doctors are veterinarians.”

Conclusion: “No radiologists are veterinarians.”

Draw radiologists as a small circle inside the doctors circle. Draw veterinarians as a separate circle that does not touch doctors. Radiologists sit inside doctors, and doctors do not touch vets, so radiologists cannot touch vets either. Answer: Yes.

Example 2

Premises: “All cardiologists are doctors. Some doctors are surgeons.”

Conclusion: “Some cardiologists are surgeons.”

Put cardiologists fully inside doctors. Now overlap surgeons with doctors and place an X in the overlap. The X could land anywhere in the overlap, including a region that excludes cardiologists. There is at least one arrangement where no cardiologist is a surgeon, so the conclusion is not forced. Answer: No.

This is the classic trap. “Some doctors are surgeons” gives you no information about whether those specific doctors are cardiologists.

Example 3

Premises: “No GPs are dentists. Some dentists are orthodontists.”

Conclusion: “Some orthodontists are not GPs.”

Draw GPs and dentists as two non-touching circles. Place orthodontists so they overlap dentists with an X in the overlap. That X represents at least one orthodontist who is a dentist. Dentists do not touch GPs, so this orthodontist cannot be a GP. There exists at least one orthodontist who is not a GP. Answer: Yes.

If you can recreate these three diagrams from memory in under 90 seconds total, your method is fast enough. If you find yourself re-reading premises, your method is still in words, not pictures.

A 20-question syllogism drill

Most students do too much DM in long blocks and lose the feedback loop. Twenty questions in 18 minutes is the right unit. That gives you 54 seconds per question with no pauses, which is roughly the live exam pace.

Run it like this:

1. Start with the two official UCAT Consortium practice tests on ucat.ac.uk. Tag every syllogism. There are not many, so harvest them.
2. Watch the official UCAT Tour videos on YouTube from the UCAT Consortium for the DM section. They show the question types in the real interface, which matters because the on-screen scratchpad changes how you draw circles.
3. Do 20 syllogisms in one timed sit. No pausing. If you do not know, mark No and move on.
4. Review for 25 minutes. For every miss, redraw the diagram on paper and write one sentence: “I assumed X when the premises only forced Y.”
5. Repeat three times across a week. By the fourth sit, your error pattern collapses into one or two recurring mistakes you can name.

If you have run out of official Consortium material and want more syllogisms at exam standard, the MasterMed free trial gives you five days of unlimited access to the DM bank without a credit card, which is enough for two or three full drill sits. Founder-honest disclaimer: it is built by one person in Australia and the question explanations are written by hand, so you get reasoning, not just “the answer is B”. The full subscription runs $3.83 a week if you decide to keep going, and the trial does not auto-bill.

The 20-question unit is calibrated for students sitting Monash, UNSW, Adelaide, UWA, Curtin, Newcastle, Western Sydney, or Flinders graduate entry. Those programmes typically want DM in the high 600s to mid 700s, and syllogisms are the most reliable place to harvest marks because the method is deterministic. Recognising a probabilistic reasoning question by feel takes weeks. Drawing two circles takes 8 seconds.

Frequently Asked Questions

How many syllogisms appear in UCAT Decision Making?

The UCAT Consortium does not publish a fixed breakdown, but DM contains 35 questions across six recognised types: syllogisms, logic puzzles, interpreting information, recognising assumptions, probabilistic reasoning, and venn diagrams. r/UCAT threads from recent test windows suggest syllogisms tend to cluster around 8 to 12 of those 35, making them the highest-volume single type.

Do I really need to draw circles in the exam?

You have an on-screen note tool and a laminated booklet. Most students draw circles on the booklet for any syllogism with three categories. For two-category questions you can hold the picture in your head, but if a question is taking more than 40 seconds, draw. The booklet is there for exactly this.

What is the difference between “some” in everyday English and “some” in UCAT logic?

In everyday English “some” usually implies “not all”. In UCAT logic “some” means at least one, possibly all. So “some surgeons are doctors” is logically consistent with “all surgeons are doctors”. This single rule resolves about a quarter of syllogism traps.

Can I solve syllogisms with truth tables instead of diagrams?

You can, but it is slower. Truth tables grow exponentially with categories, and three-category syllogisms become unwieldy under the 31-minute clock. Euler-style circles scale linearly and match how the test is constructed.

Are there free official questions I can use?

Yes. The two full mocks and question bank on ucat.ac.uk are the only fully official questions and they are free. Beyond that, the UCAT Tour series on YouTube walks through the interface and question logic at no cost. Anything beyond those two sources is third-party.

Your next step tonight

Open ucat.ac.uk, log in, find the syllogism questions inside Practice Test A, and do 10 of them with a piece of paper and a pen beside your keyboard. Draw the circles for every single one, even the easy ones. The point of the first sit is not the score. It is to make the diagram automatic before the timer ever turns on.