On dogs [not] having thoughts, do you say this based on the premise that thoughts are necessarily articulated (internally verbalized)? That seems to be a fairly popular perspective in discussions about human thought. But as to that (not to strawman or anything) I see it as just one of various forms of mental imagery[1] that can arise from something that I would say already arguably constitutes a thought.

That kind of unsymbolized thoughtform is fragile in my experience, as it strongly tends toward crystallizing into some kind of mental imagery. But I find it's possible in the right conditions to be conscious of chains of wordless, imageless propositional thoughts (by which I mean thoughts with truth values, of course, but also ones that are "propositional" in the sense of considering a plan of action or a causal chain).

Does it mean that dogs are evaluating truth conditions in the same manner but merely lack the linguistic components? I don't know; maybe that's wishful thinking. But they appear to have structured modeling/reasoning of causal and spatial relations in a way that's at least functionally equivalent to propositional thought.

1. That is, rather than just "images" or visualizations, the full spectrum of sensory/perceptual/motor emulations that can be experienced. See, for example, <https://hurlburt.faculty.unlv.edu/codebook.html>, though I'm not sure if this covers everything. I think there is, for example, a kinesthetic form of mental imagery -- which I would suggest is what coaches [don't know they] really mean when they tell you to visualize an action -- that consists of aborted motor commands that are still expressed just enough for their purpose (cf. the mostly aborted motor commands to the vocal cords, lips, etc. that can be observed in a person subvocalizing while reading).