اگر يك دليل براي انجام كاري داشته باشيد و من دليل دومي براي انجام آن كار به شما ارائه دهم منطقي به نظر مي رسد كه دو دليل بهتر از يك دليل هستند و به احتمال زياد آن كار را انجام خواهيد داد. 
If you have one reason for doing something and I give you a second reason for doing the same thing, it seems only logical that two reasons are better than one and you're more likely to do it. 