Tabby Is A Cat

The Philosophy

This session was designed to focus specifically on logic. There was a class who would agree to logically inconsistent statements without realising it (eg. 'Is it possible to think of nothing?' 'No' Did you think of nothing? 'Yes'). So the children are asked to say which sentences are consistent. In fact, the children gradually establish that all the sentences can be made to fit if you are imaginative about the context.


Best to do this session by writing sentences out on pieces of paper and laying them out on the floor. This seems to engage the children more than having the words on the board. Also, having 'your own' sentence in a group seems to motivate them too.

One sentence goes in the centre of the floor after the teacher shows it to everyone: Tabby is a cat. Then the other sentences are given out to groups of 3 or 4. Each group gets ONE sentence only.

  • Tabby eats grass.
  • Tabby is a dog.
  • Tabby is my friend.
  • Tabby can do magic.
  • Tabby doesn't exist.
  • Tabby has three legs.

You might think of others you want to try.

Task Question 1: 

  • Can your sentence and the sentence in the middle both be true?

Let the children discuss this in groups for a while. Then ask the first group to tell everyone whether they think their sentence can be true at the same time as 'Tabby is a cat'. Then let the other groups come in on that. After a while move on to another group, and their sentence. Usually you should be able to get through each group after about 20-30 minutes. Sometimes the discussion is in full swing so just carry on. Sometimes you can put them back into their groups to discuss further which of all the other sentences are consistent with the central one.

In most cases the group tends to pick up on one or two of the sentences, but you can never tell which ones. The value of the session is that the children are exploring logical argument for its own sake, and the facts (about cats!) are not in dispute at all. Here are some of the arguments children have had:

  • Tabby eats grass... It could just be a weird cat.
  • Tabby is a dog... It could be half cat, half dog. OR There are two Tabbies – one is a cat, the other is a dog. [This works for all of them; if the word Tabby has two referents then there is no problem!]
  • Tabby is my friend... It could be another cat speaking.
  • Tabby can do magic... If so, then any of the other sentences could be true too. OR Tabby can't do magic because there's no such thing as magic.
  • Tabby doesn't exist... Tabby could be dead.
  • Tabby has three legs... That can't be right because then it couldn't walk. [!]

You need to do a lot of Anchoring: 'So... does that mean they can't both be true? Or they can?'

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