WEBVTT 00:00:02.600 --> 00:00:04.880 If we want to design effectively 00:00:04.880 --> 00:00:08.960 for humans working with computers, clearly we need to understand humans. 00:00:14.400 --> 00:00:17.600 So let's talk a little bit about the nature of humans, 00:00:17.720 --> 00:00:21.733 the way we operate from our senses through to our actions. 00:00:21.920 --> 00:00:26.813 And one way to think about this is almost like a computational analogy. 00:00:26.920 --> 00:00:30.640 If you think about the computer, there's inputs to the computer, the things that you type at it; 00:00:30.760 --> 00:00:33.600 the presses you do on its surface. 00:00:33.720 --> 00:00:36.600 It does some work and it produces outputs. 00:00:36.680 --> 00:00:41.791 And one of the models for human psychology is to think like that about the human. 00:00:41.920 --> 00:00:45.360 So on the one side, you've got perception, you've got our senses, 00:00:45.360 --> 00:00:49.400 our sight, our sound and things like that that feed in. 00:00:49.480 --> 00:00:53.440 Then you've got your brain in the middle that does lots of chuntering and processing. 00:00:53.440 --> 00:00:57.576 And then it creates outputs, so physical actions but also speech, 00:00:57.576 --> 00:01:00.960 and anything else that we're using – facial expressions. 00:01:00.960 --> 00:01:06.280 So that's a model of the human, which is the input-output engine model. 00:01:06.280 --> 00:01:08.280 That can be quite powerful. 00:01:08.280 --> 00:01:12.120 You can look at those parts individually, and a lot of psychology 00:01:12.120 --> 00:01:14.920 is about focusing on one part or another part at a time 00:01:14.920 --> 00:01:17.915 and trying to make sense of what's going on there. 00:01:18.640 --> 00:01:23.739 However, that doesn't give you, shall we say, a rounded picture of the human. 00:01:24.720 --> 00:01:31.293 Because we don't just act as an output; we act in order to live our lives. 00:01:31.360 --> 00:01:35.091 There's actually a loop that goes on – a complete picture – 00:01:35.091 --> 00:01:37.547 so we might perceive something... 00:01:37.547 --> 00:01:40.400 So I might spot something I'm interested in. 00:01:40.400 --> 00:01:43.240 I might then think, "Oh, I'll go and look at it." 00:01:43.240 --> 00:01:45.400 And then perhaps I start to move off 00:01:45.400 --> 00:01:49.099 in that direction to go and have a look at the thing. 00:01:49.400 --> 00:01:52.280 If you're dealing with a computer, of course, the thing you act on typically 00:01:52.280 --> 00:01:56.120 is a computer. So maybe I'll look at my computer. I see something. 00:01:56.120 --> 00:01:58.920 I think, "Ah, I want to read my mail". 00:01:58.920 --> 00:02:01.454 I reach out and, 00:02:01.454 --> 00:02:04.520 you know, if it's a phone, I might tap the icon. 00:02:04.520 --> 00:02:09.800 If it's on my computer, I might use my touchpad and move the mouse and click the icon. 00:02:09.800 --> 00:02:13.024 And then, of course, when I click the icon, something happens. 00:02:13.080 --> 00:02:16.065 There the computer does something back. 00:02:16.120 --> 00:02:19.040 If it's the world, if I pick something up, if I throw a stone, 00:02:19.040 --> 00:02:22.680 the stone moves through the world, and I perceive 00:02:22.680 --> 00:02:25.840 the impact of my actions on the world. 00:02:25.840 --> 00:02:30.000 I might perceive that by seeing it; I might perceive it by feeling it. 00:02:30.080 --> 00:02:33.785 So there's this complete loop that goes from action 00:02:33.785 --> 00:02:38.367 through to the world, through to perception, to cognition, back to action. 00:02:38.367 --> 00:02:41.423 And when I drew it as an input/output loop, 00:02:41.423 --> 00:02:44.640 we started off with perception as if perceptions drove things. 00:02:44.640 --> 00:02:50.240 However, there's also a good argument to think starting with action. 00:02:50.240 --> 00:02:54.080 Actions might arise because of perceptions. 00:02:54.080 --> 00:02:58.287 But actually, what are we about as humans and as any animal? 00:02:58.287 --> 00:03:00.804 We're there to do things. We're there to do things, 00:03:00.804 --> 00:03:05.429 to get food for ourselves, to help us keep comfortable. 00:03:05.520 --> 00:03:07.920 So it's about *doing things in the world*. 00:03:07.920 --> 00:03:12.880 And so there's one way to perceive, to look at this picture as *input to output*, 00:03:12.880 --> 00:03:16.200 but another is to actually focus on that action, 00:03:16.200 --> 00:03:19.160 about really achieving the things that we want to achieve. 00:03:19.160 --> 00:03:23.440 Now that's true of our physical existence in the world, 00:03:23.440 --> 00:03:28.533 but also crucially, that's true when we design digital interactions.