Can you defend your thesis without any slide presentation? You speak and present your thesis without a slide presentation, probably with a pen to explain something on the board. This question came to mind when I was wondering &quot;why do we need a slide presentation?&quot; and &quot;have all thesis defenses in the world been done using a slide presentation?&quot; and &quot;will you be penalized if you defend your thesis without a slide presentation?&quot;.
Of course, slide presentations are a very recent development. Even the humble overhead projector didn't exist when I defended. We wrote with chalk on a slate like material.
Yes, you can do a presentation without slides. In some ways you can make a better presentation unless you are very skilled with slide creation. Most slide presentations are incredibly boring. They have been described, somewhat accurately, as the private notes that a speaker would normally keep to themself rather than making them visible. I know a couple of people who can do a good job, but it is, in my view a poor technology in general.
However, the expectations of your audience should be taken into account. If they expect slides, then you should probably do it that way. If you distribute the slides, printed perhaps, before the presentation then the audience has a place to take &quot;notes in context&quot;. So, the &quot;penalized&quot; question is an entirely local one. Make sure you understand the local expectations. And, don't be boring.

At one university where I studied, the chalk boards were actually slate and there was a chalk tray at the bottom. The classrooms were very seldom cleaned and after several weeks a small cone of chalk dust would be growing on the floor just below the end of the tray.
Since the boards were seldom washed, just dry wiped, it sometimes occurred that the writing on the board would start to slide down the board on the &quot;lubrication&quot; of the still remaining dust from earlier uses. It would get distorted as it slid, of course.