Não levando em conta as várias reinicializações e mudanças na linha do tempo, há duas coisas que podem explicar por que Graham não acreditava em alienígenas:
- Primeira coisa: muitos dos encontros com alienígenas são apagados da memória, seja pelos alienígenas ou por alguma outra força.
Por exemplo, você esquece o silêncio assim que você olha para longe deles. Os monges, os proprietários das pirâmides vistos na última temporada, se apagaram da memória.
De Mentira da Terra :
(Sitting on the pedestal of a now-destroyed Monk statue, just the inner metal support sticking up.)
BILL: This is exciting, isn't it? You know, kind of, it's like a turning point.
(The Doctor is pouring a drink from a thermos.)
BILL: Humans have learned that they can overthrow dictators and stuff, they just have to band together.
DOCTOR: Well, it's not quite as simple as that. You, Appalling Hair.
(A passing student looks up from her 'smart' phone.)
DOCTOR: This thing that we're sitting on. What is it?
STUDENT: Er, we thought they were just like filming something here or something?
DOCTOR: Thank you. Very helpful. Now go away, or something. You see? The Monks have erased themselves. Humanity's doomed to never learn from its mistakes.
BILL: Well, I guess that's part of our charm.
DOCTOR: No, it's really quite annoying. Anyway, I mustn't keep you. Three thousand words. The Mechanics of Free Will. Now six months overdue.
- Segundo, e talvez o mais importante, a maioria dos humanos não se importa com nenhum acontecimento estranho, grande ou pequeno, e não acreditaria de qualquer maneira.
O médico diz claramente em Journey's End :
SYLVIA: But the whole world's talking about it. We travelled across space.
DOCTOR: It'll just be a story. One of those Donna Noble stories, where she missed it all again.
Donna nobre, depois de ter sua memória apagada no mesmo episódio, não acreditaria quando sua amiga no telefone lhe contasse sobre os alienígenas que seqüestraram a Terra e a incrível visão de tantos outros planetas no céu.
DONNA: My phone's gone mad. Thirty two texts. Veena's gone barmy. She's saying planets in the sky. What have I missed now? Nice to meet you.
[...]
(Donna is on the phone.)
DONNA: How thick do you think I am? Planets. Tell you what that was, dumbo. That's those two for one lagers you gets down the offy because you fancy that little man in there with the goatee. Ha ha! Yes, you do. I've seen you.
DOCTOR: Donna? I was just going.
DONNA: Yeah, see you. I tell you what though, you're wasting your time with that one, because Susie Mair, she went on that dating site, and she saw him. No, no, no, no. Listen, listen, this is important. Susie Mair wouldn't lie. Not unless it was about calories. Ha ha ha!
Ou, em uma escala menos dramática de eventos, ninguém percebe ou se preocupa com o aparecimento de uma caixa policial azul desatualizada em um dos principais lugares em Cardiff, bem em frente ao prédio do governo galês, se eu estiver não se engane, e fica lá por algum tempo antes de desaparecer sem deixar vestígios, tudo isso em plena luz do dia. Como dito em Boom Town :
MICKEY: Wait, the Tardis, we can't just leave it. Doesn't it get noticed?
JACK: Yeah, what's with the police box? Why does it look like that?
ROSE: It's a cloaking device.
DOCTOR: It's called a chameleon circuit. The Tardis is meant to disguise itself wherever it lands, like if this was Ancient Rome, it'd be a statue on a plinth or something. But I landed in the 1960s, it disguised itself as a police box, and the circuit got stuck.
MICKEY: So it copied a real thing? There actually was police boxes?
DOCTOR: Yeah, on street corners. Phone for help before they had radios and mobiles. If they arrested someone, they could shove them inside till help came, like a little prison cell.
JACK: Why don't you just fix the circuit?
DOCTOR: I like it, don't you?
ROSE: I love it.
MICKEY: But that's what I meant. There's no police boxes anymore, so doesn't it get noticed?
DOCTOR: Ricky, let me tell you something about the human race. You put a mysterious blue box slap bang in the middle of town, what do they do? Walk past it. Now, stop your nagging. Let's go and explore.