Think of some examples. Here's a classic Thomist "analogical" term: "healthy". Properly speaking it is only bodies that are healthy, and for a body to be healthy is for it to be in good working order. For medicine to be healthy isn't for the medicine to be in good working order, it is for the medicine to have the power to put bodies into good working order. So here we clearly have two distinct but senses of "healthy".
So let's consider an example of a syllogism.
- All healthy bodies are good.
- Some medicine is healthy.
- Therefore, some medicine is good.
The occurrence of "healthy" in the major premise is the primary analogate, and "healthy" in the minor premise means "that which produces health" (secondary analogate). Do we have a valid syllogism here? According to Thomists, yes; according to Scotists and those who are suspicious of analogy, no.