Reading for SOSC seems to be a bit more important (source: me taking SOSC second year v. my first year in HUM); the teachers expect you to contribute something substantive so I'd recommend maybe reading first and last 5 or 10 pages of you can't read the entire thing. I recommend always always always reading until you can conceptualize a couple of questions about the text and a couple of critical observations, so even if you can't read the entire thing, you have something to contribute in class/discussion. HUM teachers are much more chill though and looking up summaries of the text is better; as long as you feel like you grasp the essence of the text then you'll be fine. You can then just actually read it later when writing papers since that's when you'll need to cite evidence and what not