A point of interest is that it would seem that one needs to be able to first contemplate the mitzvos and then, as a second step, decide to willingly fulfill them. One would think that if someone spent the proper time in deep contemplation or התבוננות over a matter, then automatically he would want to fulfill it or live life by its edicts; why is it a two-step process? The Sforno was not talking about reading over and taking in face value, with just a glance, each mitzvah. To contemplate, להתבונן בם means to delve into each matter. To focus on a subject and get a level of clarity so clear that one sees every angle of the matter at hand. That is the proper method to engage contemplation or reflection. However, if that is so, why then would one have to actively decide to fulfill the mitzvah after all that contemplation? It is understandable if one first has to choose to fulfill the mitzvah and then learn how to do it; but once a person has an appreciation of the beauty of the mitzvah after much concentration and study, one would think that the drive to fulfill it would be automatic!?
Imagine: a scientist or philosopher, working towards a goal for many years, who finally has a breakthrough which changes the world forever. Of course he believes in all of his research; all the time and effort, the minutia that was delved into (unless of course he is lying to himself and the rest of the world). Therefore it should be automatic that he would live by what was studied and proven for so many years!
It must be that a person has the ability to disconnect from the obvious; it must have been built into the nature of a person, and to their benefit, to need to actively decide to fulfill and run their lives according to all they have learned.