I would recommend getting an account and simply testing it directly. It's fairly easy to demonstrate that it operates at a conceptual level and is not merely predicting word probabilities in a simplistic way.
A good example with GPT is to watch it do complex math. There are simply too many permutations of math solutions for it to have ever memorized, and it can easily explain its process and the path it took to arrive at a solution.
Another good set of tests are ones around theory of mind, complex deduction problems and missing information, etc. A good source of information about the precise capabilities of GPT-4 is the Microsoft Sparks paper, which goes into a good number of tests MS researchers put the model to.
A good example with GPT is to watch it do complex math. There are simply too many permutations of math solutions for it to have ever memorized, and it can easily explain its process and the path it took to arrive at a solution.
Another good set of tests are ones around theory of mind, complex deduction problems and missing information, etc. A good source of information about the precise capabilities of GPT-4 is the Microsoft Sparks paper, which goes into a good number of tests MS researchers put the model to.