What does "take that picture" mean in this context ?

Thanks for your help.

The professor is talking about Plato's philosophy by beginning with Plato's famous work, The Republic, in which he says to some idea of what the individual human soul is like, we should study the structure of society, and every society has to have three group of people: workers, soldiers, and leaders.  ....

Professor: ... And soldiers need to channel their high spiritedness in a certain direction, precisely by being courageous.  But you're not gonna get that automatically. You need to teach them this kind of moderation.  So you need an educational system that first of all will train the leaders, so that they'll make good decisons.  Then make leaders responsible, turn over to them the education of the other two groups. And through education, build a society so that the workers and soldiers learn to use their intellect to control their desires and emotions.  If you had all that, then, for Plato, you'd have a good or just society.
    Now, take that picture - that social, political picture - and apply it to the indiviual person.     ...